Re: Ports IP specific?

[DrFranken <midrange@xxxxxxxxxxxx>]

David really has the key bit here:

> You can have one application bind itself to port 192.168.1.1:5000 and
> another application bind itself to port 192.168.1.2:5000.
>
> However, if your application binds itself to ALL IP's on port 5000
> (0.0.0.0:5000) no other application can bind itself to port 5000 on
> any IP.

Each application that binds to a port does so either to * (All IPs) or 
to a specific IP.

If it picks * then it blocks any other application from using that port 
on ANY IP address.

NOT all applications allow binding to an address they simply pick * always.

        - Larry "DrFranken" Bolhuis

www.Frankeni.com
www.iDevCloud.com - Personal Development IBM i timeshare service.
www.iInTheCloud.com - Commercial IBM i Cloud Hosting.

On 5/28/2019 9:05 AM, David Gibbs via MIDRANGE-L wrote:
> On Tue, May 28, 2019 at 7:48 AM Justin Taylor <JUSTIN@xxxxxxxxxxxxx> wrote:
> > That's what I assumed, and what Wikipedia shows.  OTOH I received a private reply saying
> > that ports must be unique across an entire server.  I guess I'll build a test and find out.
>
> Assuming you have a machine that has IP addresses 192.168.1.1 &
> 192.168.1.2 assigned...
>
> You can have one application bind itself to port 192.168.1.1:5000 and
> another application bind itself to port 192.168.1.2:5000.
>
> However, if your application binds itself to ALL IP's on port 5000
> (0.0.0.0:5000) no other application can bind itself to port 5000 on
> any IP.
>
> david